The aims of this work were to determine the color change and physical–mechanical properties of polystyrene glulam from three tropical wood species. Wood laminas were cut from logs harvested from a young plantation forest of manii (Maesopsis eminii), mangium (Acacia mangium), and rubber-wood (Hevea brasiliensis). The laminas were impregnated with monomer styrene that was polymerized using potassium peroxy-disulfate as a catalyst and heat. Three-layer glulam was constructed from the polystyrene laminas, using isocyanate glue and cold press. For comparison purposes, three-layer untreated glulam and solid wood samples were prepared. The results showed that the color change of polystyrene glulam was very small compared with untreated glulam. Polystyrene glulam had the highest density, while the density of untreated glulam did not differ from that of the solid wood. The moisture content of all products was matched to the environment, and fulfilled the Japanese standard. Compared with both types of glulams, solid wood had lower values for modulus of rupture (MOR), modulus of elasticity (MOE), and hardness, but higher shear strength. Meanwhile, polystyrene glulam had lower values for MOR and MOE, equal shear strength and wood failure, and higher hardness than the untreated glulam. All glulams had very little delamination in the hot water test. Only rubber-wood glulams fulfilled JAS 234-2003 for MOR, MOE, shear strength, and delamination. To obtain adequate physical–mechanical properties of glulams, medium-density wood is recommended for glulam manufacturing.

Short rotation teak (SRT) has a diameter of around 30 cm at the age of 15 years; however, the wood still has low quality, especially in dimensional stability and biological durability. The objective of this study was to improve dimensional stability and biological durability of SRT through modification treatment using non-biocide chemicals, citric acid (CA) and benzophenone tetracarboxylic acid (BPTCA). SRT sapwood was impregnated by 20% and 40% of CA or BPTCA followed by heating in the oven at 150 °C for 2 h. Dimensional stability, strength, surface characteristics and durability against termite attacks of the modified woods were evaluated. Results show that dimensional stability as anti-swelling efficiency (ASE) increased by an average of 46% (CA) and 50% (BPTCA) after treatments. Durability against termites showed that the modified woods were categorized to be class 1 (very durable). Fourier Transform Infrared (FTIR) and X-ray Diffraction observations indicated a possible chemical reaction between the wood components with CA and BPTCA. The water-based acrylic and oil-based alkyd contact angle values of the modified woods were lower than 90°, indicating their high wetting ability against the varnish liquids. The treatment can be applied to improve the quality of SRT for high-quality wood product utilization.

This report presents result of a study on air drying properties and kiln drying schedule of ten wood species from Nusa Tenggara Barat. the study was carried out based On data from quick drying test. The result shows that, the quality of almost all of the species dried using air drying method are inferior compared with that obtained from kiln drying. the ten wood species used in the study can be grouped into four drying schedules, ringin, kabaukafa, sabaha and niu can be grouped into schedules 1 (easy to dry), katowi and kencari schedule 2, whereas red monggo and konca schedule 3, and mongo schedule 4 (difficult to dry).

SIFAT FISIS DAN PENGERINGAN LIMA JENIS BAMBU

A moisture-content based on drying schedule provides general guidance in determining the changes in temperature and humidity which is based on the average moisture content level of the wood being dried. The research aims to obtain a basic drying schedule for seven wood species based on their drying characteristics. The research is initiated by drying all these species at a temperature of 100 °C. The criterion used is the worst defect occurred in each wood such as end and surface, honeycomb defects, and deformation on the width of the wood. The result shows that each wood species has a different response to high temperature drying. The best drying properties is observed in Red Meranti wood (Parashorea smythiesii) and Jaha wood (Terminalia arborea). In contrary, Kiacret (Spathodea campanulata) and Kipasang (Prunus javanica) have the worst drying properties. Based on their drying properties, all of the species can be grouped into 4 drying schedules.